Infection after total knee arthroplasty

TLDR

The study aimed to assess current incidence and outcomes of infected total knee arthroplasty in our unit compared to a 1986 audit. The authors implemented strict antibiotic prophylaxis, laminar flow theatre protocols, and chlorhexidine lavage, then followed 931 primary and 69 revision TKAs for a mean 6.5 years via questionnaires, interviews, and case notes. Infection occurred in 1 % of primary and 5.8 % of revision TKAs; primary infections were mostly resolved without further surgery, whereas all revision infections led to poor outcomes, and despite reduced infection rates, overall outcomes have improved little.

Abstract

The aim of our study was to determine the current incidence and outcome of infected total knee arthroplasty (TKA) in our unit comparing them with our earlier audit in 1986, which had revealed infection rates of 4.4% after 471 primary TKAs and 15% after 23 revision TKAs at a mean follow-up of 2.8 years. In the interim we introduced stringent antibiotic prophylaxis, and the routine use of occlusive clothing within vertical laminar flow theatres and 0.05% chlorhexidine lavage during arthroplasty surgery. We followed up 931 primary TKAs and 69 revision TKAs for a mean of 6.5 years (5 to 8). Patients were traced by postal questionnaire, telephone interview or examination of case notes of the deceased. Nine (1%) of the patients who underwent primary TKA, and four (5.8%) of those who underwent revision TKA developed deep infection. Two of nine patients (22.2%) who developed infection after primary TKA were successfully treated without further surgery. All four of the patients who had infection after revision TKA had a poor outcome with one amputation, one chronic discharging sinus and two arthrodeses. Patients who underwent an arthrodesis had comparable Oxford knee scores to those who underwent a two-stage revision. Although infection rates have declined with the introduction of prophylactic measures, and more patients are undergoing TKA, the outcome of infected TKA has improved very little.